Effects of commercial enzymes on proteolysis and ripening in Cheddar cheese

The effects of exogenous enzyme preparations, ie FlavourAge-FR or DCA 50, on proteolysis flavour texturai development in high (38%) or low (35%) moisture Cheddar cheeses ripened at 4 or 10°C for 180 days were investigated. Proteolysis, as measured by nitrogen soluble in water (WSN), 75% ethanol (ALC-N) or 5% PTA (PTA-N), was highest in cheeses with added FlavourAge-FR, intermediate in DCA 50-treated cheeses and lowest in control cheeses at both 4 or 10°C. The WSN was chromatographed by fast protein liquid chromatography (FPLC) and free amino acid analysis. The concentrations of low molecular weight (< 10000) peptides and free amino acids were highest in FlavourAge-FR-treated cheeses while DCA 50-treated cheeses had intermediate levels compared to control cheeses at 4 or 10 oC. Polyacrylamide gel electrophoresis of the cheeses during ripening showed that FlavourAge-FR caused significant proteolysis of both α51- and p-caseins, while DCA 50 caused no significant degradation of p-casein. Cheese texture, as measured by yield value, was affected most by FlavourAge-FR treatrnent. Taste panel analysis of the cheeses indicated Iittle acceleration of flavour development by any of the treatments, and in some cases enzyme treatment led to off-flavours and textural defects

Cheesemaking, compositional and functional characteristics of low-moisture part-skim mozzarella cheese from bovine milks containing j-casein AA, AB or BB genetic variants

Summary. Low-moisture part-skim Mozzarella cheeses were made, at pilot scale (450 kg), on five occasions at weekly intervals from milks containing j-casein AA, AB or BB genetic variants. Compared with j-casein A variant milks, the j-casein B variant milks were associated with higher concentrations of casein (P<0.001), whey protein (P<0.02) and total protein (P<0.001), superior curd-forming properties (P<0.05) and increased cheese yields (P<0.05). The moisture-adjusted (to 465 g/kg) cheese yields for the j-casein AA, AB and BB cheeses were 91.5, 100.6, and 102.5 kg/1000 kg milk respectively. j-Casein variant had no significant effect on the proteolysis and ripening of uncooked cheese or on the functionality (melt time, fowability and stretchability) of the cooked cheese during the course of a 90 d ripening perio

Integration of high and low field H-1 NMR to analyse the effects of bovine dietary regime on milk metabolomics and protein-bound moisture characterisation of the resulting mozzarella cheeses during ripening

The influence of dairy cow feeding regime was investigated using H-1 nuclear magnetic resonance (NMR). Two different NMR analytical systems were deployed: high field H-1 NMR to investigate the influence on milk metabolomics and low field NMR to characterise proton relaxation linked to changes in the state of mozzarella cheese moisture during ripening. The metabolomics results showed that grass-based feeding increased the concentration of a biological marker that signifies near-organic milk production conditions. On the other hand, the investigation of cheese moisture distribution showed that grass-based diets reached final moisture partitioning in a shorter time, which implied the formation of a more compact protein structure in the cheese matrix. These results indicate that pasture-based dairying may be differentiated in terms of the provenance of milk produced along with the accrual of additional benefits during ripening of the resulting mozzarella cheeses. (C) 2018 Elsevier Ltd. All rights reserved